如图，

$\because \angle ABD=20^{\circ}$，
$\therefore \angle ABC=70^{\circ}$，
$\therefore$点$A$在点$B$的北偏西$70^{\circ}$.
故答案为：北偏西$70^{\circ}$.

如图，

$\because \angle ABD=20^{\circ}$，
$\therefore \angle ABC=70^{\circ}$，
$\therefore$点$A$在点$B$的北偏西$70^{\circ}$.
故答案为：北偏西$70^{\circ}$.